Tsunehisa Ryo-Deba Aogami #2 Kuro-uchi 165mm (6.5″)

Easily one of the most badass deba knives in our collection, this Tsunehisa Ryo-Deba Aogami #2 Kuro-uchi 165mm (6.5″) is for serious fish fans (and chefs!) with some arm strength—after all, at 290g (10.2 oz), wielding it is not a walk in the park. 

This deba stands out from most other (typically single-bevel) deba knives with its double bevel quality, meaning this deba is a Ryo-Deba knife. The double-bevel quality means easier sharpening, but also makes it ideal for heavy-duty tasks such as cutting through bones of large fish and chicken. Due to its symmetrical blade, it is suitable for both right- and left-handed users.

Tsunehisa Ryo-Deba Aogami #2 Kuro-uchi 165mm (6.5″) is a Japanese kitchen knife specialized for fish preparation. It is designed for heavy-duty work of skilled professionals, or experienced home users. It is especially recommended for “big game” fishing enthusiasts!

Traditional Japanese knives are made from steel high in carbon, and this is mainly for two reasons: due to the steel’s pure composition, the blades can achieve an extremely fine sharpness, for the same reason, they can be easily resharpened back to optimal shape. Aogami #2 is one of the best in the high-carbon class, with added elements such as chromium (Cr) and tungsten (W) for improved corrosion and wear resistance, all while having an awesomely fine sharpness and being able to get resharpened easily.

BLADE SHAPE:
Deba is one of the »big three« Japanese traditional kitchen knives, alongside usuba and yanagiba. They are essentials that every sushi chef needs to master.
Deba is a traditional knife a chef uses to prepare a whole fish: anything from cleaning, filleting, portioning fish, removing fins and heads, to chopping through smaller bones. It can also be used for preparing poultry and other meat with smaller bones.
The deba knife is a well-balanced blend of robustness and precision. Filleting fish can be tricky and requires precise maneuvering, so using a sharp deba is essential in reducing the risk of damaging the delicate fish flesh.
The thick and heavy blade equips the deba for heavy-duty work that requires force – removing fins, tails, and fish heads, along with breaking down smaller bones.
This deba is special – it is a ryo-deba, meaning that it has a double bevel grind (unlike most deba knives), so it can be used by both right- and left-handed users. The double-bevel quality will also allow for easier sharpening. A ryo-deba can handle heavier tasks such as cutting through bones of large fish and chicken with ease.

STEEL:
Aogami #2 is a very popular steel in Japanese knife making and one of the finest high-carbon steels, meaning the knives forged from it will have exceptional edge retention and also sharpen very easily. At the same time, it is less resistant to corrosion, meaning the blade can develop a patina, while longer exposure to water or other corrosives could also lead to rusting. This is improved to some extent with the addition of chromium and tungsten, but it’s still a high-carbon steel that should be maintained accordingly (⚠️ read more about knife maintenance here). Aogami #2 steel is composed of carbon (C) 1.1 %, chromium (Cr) 0.5 %, manganese (Mn) 0.3%, and tungsten (W) 1.5%.

LAMINATION:
The blade’s core was laminated using the san-mai method to improve its structural integrity and subsequent ability to withstand impacts and prevent chipping. San-mai translates to “three layers” in Japanese, referring to a blade that is composed of a primary, inner layer of harder steel (hagane) and of two secondary, outer layers of softer steel (jigane) that protect the prior.

→ Read more on Blade Construction: Lamination.

GEOMETRY:
The knife is a double-bevel blade with a convex v-edge. It is heavier and stronger at the handle and thinner and more precise at the tip, towards which it tapers. This blade shape makes the knife easier to use because it is very responsive, easily maneuverable, and nicely balanced. This type of blade design is called distal taper – you can read more about it in the article on blade geometry.

BLADE FINISH:
The blade has a kuro-uchi blade finish. The Kuro-uchi finish on Aogami #2 blades provides a protective layer against rust and other external elements that can otherwise damage the surface. The kuro-uchi finish (kuro – ‘black’) is a layer of raw, protective patina on the outer steel. It gets a nice contrast from the hand-chiseled kanji on the blade. The kireha (lower part of the blade or ‘blade road’) has a classic cloudy kasumi finish.

HANDLE:
Japanese (Wa) style handle is made out of rosewood and is topped with a black pakka wood ferrule. The oval handle allows a comfortable and firm grip, suitable for both left- and right-handed users.

A traditional feature of wooden handles is that over time the soft surface of the wood will lose its smoothness and shine, giving it an even better grip and making it even safer to use with wet hands. This extra friction of the “roughened” surface ensures that greasy, wet, and slippery palms don’t slide forward on the blade during use.

THE SMITHY:
Tsunehisa knives are a brand that combines a variety of high-quality knives from various knife centers of Japan such as Tosa, Seki, and Sakai. Their philosophy is that each region has its own steel and different manufacturing processes. For example, Tosa is best known for its Ginsanko and Aus-8 steels, Seki is famous for making excellent blades from the V-Gold group of steels, and Sakai is famous for its single-beveled Honyaki knives.